CN111246484A - Spectrum self-adaptive high-performance communication system and method - Google Patents

Abstract

The invention relates to a frequency spectrum self-adaptive high-performance communication system and a frequency spectrum self-adaptive high-performance communication method, which are suitable for multifunctional dynamic reconstruction and frequency spectrum self-adaptive high-performance communication of communication equipment under various occasions such as ground, aviation, aerospace and the like. The invention realizes the spectrum self-adaptive communication function under the condition of interference in the communication process and improves the spectrum resource utilization efficiency and the communication efficiency of satellite communication.

Description

A spectrum adaptive high-performance communication system and method

technical field

The invention relates to a spectrum adaptive high-performance communication system and method, belonging to the technical field of civil communication and the general technical field of aerospace.

Background technique

At present, the communication spectrum resources are limited and the utilization rate is low, and the global communication is faced with the urgent need to improve the reliable communication capability under the electromagnetic environment interference. The communication system is seriously interfered by other radio equipment during the communication process, and the channel blockage and communication interruption problems occur frequently, which seriously reduces the availability of the communication system, and cannot effectively exert its economic and social benefits. The reliable communication technology in the complex electromagnetic environment needs a breakthrough. Civil application requirements such as civil disaster reduction and prevention, emergency rescue, and emergency response to abnormal events are urgently needed for communication systems such as spectrum adaptive high-performance communication functions and heterogeneous networking.

In response to the above-mentioned extensive application requirements and technology development trends, there are communication anti-jamming methods such as adaptive filtering and nulling antenna technology based on space or time domain, and adaptive coding technology. Evaluating spectrally adaptive high-performance communication methods. In addition, in terms of the multi-function of "one type and multi-purpose" equipment, multiple sets of equipment are widely used in the world to realize broadband spectrum monitoring, communication broadcasting, and data transceiver and other functions, but there is no solution based on a set of general hardware platform. It is a technology that realizes the dynamic reconstruction and parallel application of the multi-functional combination of broadband spectrum monitoring, signal analysis and processing, and communication functions.

SUMMARY OF THE INVENTION

The technical problem solved by the present invention is: to overcome the deficiencies of the above-mentioned prior art, to provide a spectrum adaptive high-performance communication system and method, aiming at using only one set of general hardware platform, without prior knowledge, to solve the problem of wideband signal sampling After the wideband spectrum monitoring, wideband multi-signal real-time fast search and detection, the number of channels based on polyphase filtering and dynamic digital channelization processing with variable bandwidth, etc., to achieve broadband spectrum monitoring, signal analysis and processing, communication functions and other functions Combining dynamic reconfiguration with application targets for parallel applications, and spectrum adaptive high-performance communication capabilities.

The technical scheme solved by the present invention is: a spectrum adaptive high-performance communication system, comprising: a receiving antenna module, a down-conversion module, a digital channelization and processing evaluation module, an adaptive up-conversion module, and a transmitting antenna module;

The receiving antenna module receives the RF signal in real time from the space, and after completing the signal amplification processing, it is sent to the down-conversion module, and the down-conversion module performs down-conversion to obtain an intermediate frequency signal, which is sent to the digital channelization and processing evaluation module;

The digital channelization and processing evaluation module obtains a digital signal after analog-to-digital conversion of the intermediate frequency signal, performs channelization processing on the digital signal, and obtains multi-channel channelized data; performs parameter measurement and modulation pattern identification for each channel of channelized data Then, obtain each channelized data characteristic parameter (each channelized data characteristic parameter, including: modulation pattern, etc.), perform adaptive signal demodulation and decoding according to each channelized data characteristic parameter, and obtain demodulation and decoding information; According to the measurement results of the characteristic parameters of the channelized data, the identification accuracy rate of the modulation pattern is determined; the demodulation bit error rate is determined according to the demodulation and decoding information; the interference rate of each channel is determined according to the identification accuracy rate of the modulation pattern and the demodulation bit error rate. If there is interference, output the interference flag, if not, output the channelized data of the channel and send it to the adaptive up-conversion module;

The digital channelization and processing evaluation module detects the available frequency points of the digital signal after analog-to-digital conversion, that is, searches for the available frequency points within the set intermediate frequency bandwidth, establishes the available frequency point resource library, and sends it to the adaptive up-conversion module.

The adaptive up-conversion module modulates the channelized data output from the digital channelization and processing evaluation module to the available frequency within the intermediate frequency bandwidth after digital-to-analog conversion according to the available frequency point resource library established by the signal detection and spectrum monitoring unit. At the frequency point, the radio frequency signal is obtained after up-conversion, and the power is amplified, and then transmitted to the space through the transmitting antenna module.

Preferably, the digital channelization and processing evaluation module includes: an intermediate frequency digitization unit, a channelization unit, a pattern recognition unit, an adaptive demodulation unit, an information processing and link evaluation unit, and a signal detection and spectrum monitoring unit.

Preferably, the intermediate frequency digitizing unit performs analog/digital conversion on the intermediate frequency signal, and the obtained digital signal is sent to the channelization unit, the signal detection and spectrum monitoring unit.

Preferably, the channelization unit performs channelization processing on the digital signal output by the intermediate frequency digitization unit to obtain the channelization data of the multi-channel signal, and sends it to the pattern identification unit; each channelization data corresponds to the input signal of the corresponding channel.

Preferably, after the pattern identification unit performs parameter measurement and modulation pattern identification on the multi-channel channelization data output by the channelization unit, the characteristic parameters of each channel of signals are obtained and sent to the adaptive demodulation unit, and at the same time, the obtained channelization data of each channel is sent to the adaptive demodulation unit. to the information processing and link evaluation unit.

Preferably, the adaptive demodulation unit performs adaptive signal demodulation and decoding according to the characteristic parameters of each channel of signals and the corresponding channelization data output by the pattern recognition unit, to obtain demodulation and decoding information, and then converts the demodulation and decoding information and the signal characteristic parameters. and channelized data to the information processing and link evaluation unit.

Preferably, the information processing and link evaluation unit determines the identification accuracy rate of the modulation pattern according to the characteristic parameters of each channelized data; determines the demodulation bit error rate according to the demodulation and decoding information; Adjust the bit error rate to judge the interference degree of each channel. If it is interfered, output the interference flag. If it is not interfered, output the channelized data of the channel and send it to the adaptive up-conversion module.

Preferably, the digital channelization and processing evaluation module further includes: a signal detection and spectrum monitoring unit, for the signal output by the intermediate frequency digitizing unit, based on the broadband multi-signal real-time rapid detection technology, the signal is carried out according to the set frequency interval within the intermediate frequency bandwidth. Detection, by judging whether the signal on each frequency point has interference, determining the available frequency point and the unavailable frequency point, establishing the available frequency point resource library, updating in real time, and sending the available frequency point resource library to the adaptive up-conversion module.

Preferably, the adaptive up-conversion module performs adaptive processing according to the interference flag output by the signal processing and link evaluation unit: if there is an interference flag, it means that it is interfered, select an available frequency point from the available frequency point resource library or adjust the communication parameters ; If there is no interference, digital/analog conversion is performed directly on the channelized sampling data of each channel, and the converted signal is up-converted and sent to the transmitting antenna module.

Preferably, the signal detection and spectrum monitoring unit is combined with the down-conversion module and the intermediate frequency digitizing unit, which can realize real-time spectrum sensing of signals in the whole frequency band of communication, obtain information of available communication frequency points, and establish an available frequency point resource library;

Preferably, the information processing and link evaluation unit, combined with the pattern recognition unit, the adaptive demodulation unit, the channelization unit, and the intermediate frequency digital unit, based on the signal analysis and processing function, can decode the modulation pattern, characteristic parameters, demodulation and decoding of the current communication signal. Statistical analysis of information to evaluate communication links;

Preferably, the digital channelization and processing evaluation module, once it is found that the current communication link is interfered and cannot communicate normally, the adaptive frequency up-conversion module informs the sender and receiver of the communication link through a dedicated signaling channel to re-select from the available frequency point library Communication frequency, communication rate, modulation mode and other parameters to re-establish the communication link.

A spectrum adaptive high-performance communication method of the present invention, the steps are as follows:

(1) The receiving antenna module receives the RF signal in real time from the space, and after completing the signal amplification processing, it is sent to the down-conversion module, and the down-conversion module performs down-conversion to obtain an intermediate frequency signal, which is sent to the digital channelization and processing evaluation module;

(2) The digital channelization and processing evaluation module, after performing analog-to-digital conversion on the intermediate frequency signal, obtains a digital signal, and performs channelization processing on the digital signal to obtain multi-channel channelized data;

(3) After parameter measurement and modulation pattern identification are performed on each channel of channelized data, characteristic parameters of each channel of data are obtained;

(4) performing adaptive signal demodulation and decoding according to the characteristic parameters of each channelized data to obtain demodulation and decoding information;

(5) According to the measurement results of the characteristic parameters of the channelized data of each channel, determine the identification accuracy rate of the modulation pattern;

(6) according to the demodulation decoding information of step (4), determine the demodulation bit error rate;

(7) According to the identification accuracy rate of the modulation pattern in step (5) and the demodulation bit error rate in step (6), determine the interference level of each channel, if it is interfered, output the interference flag, if not, output the channel The channelized data is sent to the adaptive up-conversion module;

(8) The digital channelization and processing evaluation module detects the available frequency points of the digital signal after analog-to-digital conversion, that is, searches for the available frequency points within the set intermediate frequency bandwidth, establishes the available frequency point resource library, and sends it to the adaptive network. Frequency conversion module.

(9) The adaptive up-conversion module modulates the channelized data output from the digital channelization and processing evaluation module to the intermediate frequency bandwidth after digital-to-analog conversion according to the available frequency point resource library established by the signal detection and spectrum monitoring unit. At the available frequency points in the device, the radio frequency signal is obtained after up-conversion, and the power is amplified, and then transmitted to the space through the transmitting antenna module.

The advantages of the present invention compared with the prior art are:

(1) The present invention is a spectrum-adaptive high-performance communication system based on a set of general hardware platforms and through software deployment to realize function redefinition and dynamic reconfiguration. The system can be defined by software to realize dynamic reconfiguration and parallel application of broadband spectrum monitoring, signal analysis and processing, and communication functions.

(2) The present invention is based on the real-time and efficient signal analysis and processing capability of wideband spectrum, real-time monitoring of communication working frequency bands, real-time evaluation of communication links, adaptive adjustment of communication parameters and communication strategies under the condition of communication interference, and real-time switching of communication frequency points, Thus, the normal communication function is ensured, and the spectrum adaptive high-performance communication is realized.

(3) The present invention effectively combines broadband spectrum monitoring, high-efficiency signal analysis and processing and communication functions, so that the communication capability of the communication system is significantly improved, and the spectrum resource utilization efficiency of the communication system and the transmission rate of data information are also improved, It is an effective way for the communication system to realize "easy to use, easy to use and reliable use".

(4) The present invention only uses a set of general hardware platform, and can realize the dynamic reconstruction and parallel application capability of the combination of broadband spectrum monitoring, signal analysis and processing, communication functions and other functions in the wide bandwidth spectrum range. While significantly improving the resource utilization rate of the software and hardware platform, the system has the new technical effect of multi-functional dynamic reconfiguration and parallel application.

(5) The present invention is suitable for multi-functional dynamic reconstruction and spectrum adaptive high-performance communication of communication equipment in various occasions such as ground, aviation, and aerospace.

(6) The present invention is based on the wideband spectrum detection function of the signal detection and spectrum monitoring unit, and can also be used for real-time detection of interference signals in a complex and multi-interference signal environment, to determine the source of interference signals and the degree of interference, so as to ensure the normal operation of communication equipment or terminals provide assurance.

(7) The digital channelization and processing evaluation module of the present invention has multifunctional reconfigurability, the functions of a channelization unit, a pattern recognition unit, an adaptive demodulation unit, an information processing and link evaluation unit, and a signal detection and spectrum detection unit All are realized by software, and different functions are realized according to different software function combinations.

(8) The present invention can realize the communication function by loading channelization, information processing and link evaluation.

(9) The present invention can realize the function of signal analysis and processing by loading channelization, modulation pattern identification, adaptive demodulation, information processing and link evaluation.

(10) The present invention realizes the real-time monitoring of the broadband spectrum by loading the signal detection and spectrum monitoring, and the real-time fast detection technology of broadband multi-signal.

(11) The present invention can realize adaptive high-performance communication by loading channelization, modulation pattern identification, adaptive demodulation, information processing and link evaluation, signal detection and spectrum monitoring.

(12) The present invention combines the use of broadband signal scanning and high-performance receiving and sensing capabilities to monitor the idle frequency spectrum in the working frequency band in real time, and evaluate the current communication link in real time. Complete spectrum adaptive high-performance communication.

(13) The high-performance communication of the present invention is embodied in the broadband multi-signal fast detection technology to achieve efficient spectrum monitoring; according to the monitoring results, an available frequency point resource library is established and updated in real time; the modulation pattern recognition accuracy rate and the demodulation bit error rate are used to comprehensively judge Communication interference situation; preferably, the communication strategy can also be adaptively adjusted, frequency points or communication parameters can be adjusted to ensure stable communication.

Description of drawings

1 is a schematic block diagram of a spectrum adaptive high-performance communication of the present invention;

Fig. 2 is the digital channelization schematic diagram of the present invention;

Fig. 3 is the spectrum monitoring schematic diagram of the present invention (taking the operation of a single frequency point as an example);

Fig. 4 is the modulation identification processing flow chart based on feature extraction of the present invention;

Fig. 5 is the channel-associated signaling format of the present invention;

FIG. 6 is a schematic flow chart of the spectrum adaptive high-performance communication according to the present invention.

Detailed ways

The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

The present invention is a spectrum adaptive high-performance communication system, which relates to the technical field of civil communication and the general technical field of aerospace. The patent of the present invention is suitable for multi-functional dynamic reconstruction and spectrum adaptive high-performance communication of communication equipment in ground, aviation, aerospace and other occasions, mainly including receiving antenna module, down-conversion module, digital channelization and processing evaluation module, transmission Antenna module, adaptive up-conversion module and other five parts. The method is based on a set of radio general hardware platform, combines broadband spectrum monitoring function, signal analysis and processing function, communication function and other functions with parallel application, utilizes high-performance signal receiving capability, and realizes real-time spectrum monitoring in a large-bandwidth working frequency band. It also evaluates the current communication link in real time, and when it is found that the link or signal is interfered, it adaptively selects and adjusts communication parameters to achieve spectrum adaptive high-performance communication. The invention provides the multi-function parallelization of broadband spectrum monitoring function, signal analysis and processing function, communication function, etc., as well as the specific scheme and implementation steps of spectrum adaptive high-performance communication, and solves the problem of high-performance, high-reliability and communication in complex electromagnetic environment. Technical problems such as multi-functional use with spectrum monitoring have improved the usability, usability and practicality of satellite communication. When the communication process is interfered, the spectrum adaptive communication function is realized, and the spectrum resource utilization efficiency and communication efficiency of satellite communication are improved.

The present invention is a spectrum adaptive high-performance communication system, which is especially suitable for the general technical field of aerospace, and the present invention is suitable for technical fields such as ground, aviation, and aerospace. Such as: civil disaster mitigation and prevention, emergency rescue, emergency response to abnormal events, etc., there is an urgent need for applications such as spectrum adaptive high-performance communication functions, spectrum real-time monitoring functions, and heterogeneous networking functions of communication systems. In these application scenarios, the multi-functional dynamic reconstruction of communication equipment and the high-performance communication function of spectrum adaptation solve the technical problems of high performance, high reliability, multi-functional communication and spectrum monitoring in complex electromagnetic environment, and improve satellite communication. usability, usability, and practicality. When the communication process is interfered, the spectrum adaptive communication function is realized, and the spectrum resource utilization efficiency and communication efficiency of satellite communication are improved.

A spectrum adaptive high-performance communication system of the present invention is a set of parallel systems with two functions of communication and spectrum monitoring. , adaptive demodulation unit, information processing and link evaluation unit to realize the communication function; the other one is sent to the signal detection and spectrum detection unit to detect the signal in the communication bandwidth, and find the free spectrum and available frequency points; the adaptive up-conversion module according to The output results of the two functions adjust the communication parameters adaptively to ensure the stability of the communication, as shown in Figure 1.

In the spectrum adaptive high-performance communication system of the present invention, the receiving antenna module may only include the receiving antenna, and the preferred solution is to include the receiving antenna and the function selection unit; when the function selection unit is provided, three working modes can be set, respectively. For communication mode, spectrum detection mode, spectrum adaptive high-performance communication mode;

In the communication mode: the information processing and link evaluation unit, combined with the pattern recognition unit, the adaptive demodulation unit, the channelization unit, and the intermediate frequency digital unit, perform analog-to-digital conversion and channelization processing on the intermediate frequency signal obtained by the down-conversion digital module, and obtain The multi-channel channelized data is sent to the adaptive up-conversion module through the information processing and link evaluation unit. After the digital-to-analog conversion and up-conversion are completed, the radio frequency signal is obtained, and then the radio frequency signal is subjected to power amplification, and is transmitted to the space through the transmitting antenna module. communication function.

In spectrum detection mode: the signal detection and spectrum monitoring unit, combined with the down-conversion module and the IF digitizing unit, detect the available frequency points of the digital signal after analog-to-digital conversion, that is, search for the available frequency points within the set IF bandwidth, and establish the available frequency points. The frequency point resource library is sent to the adaptive up-conversion module to realize real-time spectrum detection of signals in the whole frequency band of communication.

In the spectrum adaptive high-performance communication mode: the digital channelization and processing evaluation module, combined with the down-conversion module and the adaptive up-conversion module, once it is found that the current communication link is interfered and cannot communicate normally, the adaptive up-conversion module passes the dedicated signal. The channel informs the sender and receiver of the communication link to re-select the communication frequency, communication rate, modulation mode and other parameters from the available frequency library, re-establish the communication link, and realize the spectrum adaptive high-performance communication function.

The above three working modes can be used alone or in parallel, which saves hardware resources and improves communication quality, and solves the problem of high performance, high reliability, communication and spectrum monitoring in complex electromagnetic environments. and other technical problems.

A spectrum adaptive high-performance communication system of the present invention judges the interference degree of each channel according to the identification accuracy rate of the modulation pattern and the demodulation error rate, and outputs the interference flag if it is interfered. Channelized data for the channel. The preferred situation is that when the demodulation error rate is higher than 10 ^-1 , it can be determined that the channel is interfered. Another preferred situation is that the identification accuracy rate of the modulation pattern is lower than 80%, and it is also determined that the channel is interfered.

频率f(m)、调制样式、码速率等参数。根据各路信道化数据特征参数，确定调制样式的识别正确率。正常通信过程中，调制样式保持不变，一旦受到干扰，调制样式会发生变化或者根本无法识别，通过统计分析通信过程中的调制样式识别正确率，可以对该信道的受干扰情况进行判断，当调制样式识别正确率低于80％时，认为受到干扰。The channelized data characteristic parameters preferably include: in-phase data I(m) and quadrature data Q(m)), amplitude value a(m), phase value as shown in FIG. 4

Parameters such as frequency f(m), modulation style, code rate, etc. According to the characteristic parameters of each channelized data, the identification accuracy rate of the modulation pattern is determined. In the normal communication process, the modulation pattern remains unchanged. Once interfered, the modulation pattern will change or cannot be recognized at all. By statistical analysis of the modulation pattern recognition accuracy during the communication process, the interference situation of the channel can be judged. When the correct rate of modulation pattern recognition is lower than 80%, it is considered to be disturbed.

The available frequency point detection is performed on the digital signal after analog-to-digital conversion. The preferred solution is: taking the frequency point of the intermediate frequency signal as the center, within the set bandwidth, perform a search for the available frequency point to determine the available frequency point. Frequency points higher than the receiving sensitivity are occupied or interfered, and are defined as unavailable frequency points, and available frequency points refer to frequencies that are not occupied.

For communication, there will be multiple communication signals in the intermediate frequency bandwidth. In order to further determine the interference signal in the communication process, the preferred solution is: first convert the intermediate frequency signal through analog/digital conversion (high-speed A/D in Figure 4). Digitize, and then channelize the IF digital signal to separate multiple communication signals within the IF bandwidth, each channelized data corresponds to a communication signal: control the digitally controlled oscillator based on different tuning frequencies (NCO in Figure 4) , separate the multi-channel signals in the intermediate frequency digital signal, and carry out orthogonal transformation (cos and sin in Figure 4), based on the multi-rate digital signal processing (MRDSP in Figure 4) technology, complete the channelization processing of the signal, A schematic diagram of the channelization processing results is shown in Figure 2.

频率f(m)，进而对信号的调制样式和码速率等参数进行估计。自适应解调单元根据样式识别单元的调制样式识别和码速率等参数，对当前信道中的信号进行解调，获取信号的误码率。The pattern recognition unit extracts the instantaneous feature parameters of the channelized data, and obtains the quadrature sampling data (I(m) and Q(m) in Figure 4) and the amplitude value a(m) of each communication signal (corresponding to the channelized data). , phase value

The frequency f(m) is used to estimate the parameters such as modulation pattern and code rate of the signal. The adaptive demodulation unit demodulates the signal in the current channel according to the modulation pattern recognition and code rate parameters of the pattern recognition unit, and obtains the bit error rate of the signal.

The information processing and link evaluation unit evaluates the interference situation of the communication signal in the current channel. On the one hand, it evaluates according to the transformation of the modulation pattern. The preferred scheme is: the modulation pattern of the current signal changes from BPSK (frequency shift keying) To FSK (phase shift keying), it is considered that the current communication signal is disturbed. On the other hand, the demodulation error rate of the signal is evaluated. For example, the current demodulation error rate changes from 10 ^-5 to 10 ^-2 , Then it is considered that the current communication signal is disturbed.

The signal detection and spectrum monitoring unit is preferably based on multi-signal real-time detection technology. For each channelized frequency point, Fs/4D, 3Fs/4D...15Fs/4D in Figure 2, where Fs is the sampling frequency, and D is the channelization channel. number, D=8 in the figure, carry out real-time signal detection, and establish an available frequency point library, find that the frequency point is available (Fs/4D is preferred in Figure 3), and then carry out the storage operation, and find that the signal is disturbed (k in Figure 3). *Fs/4D, k=1,3,5...15) removed from the library.

The adaptive up-conversion module adaptively adjusts the current communication strategy according to the output interference flag and the available frequency library. Display) to notify the communication double-transmission switching frequency point, if not interfered, maintain the current communication status, and continue to monitor.

Figure 6 shows the communication flow chart of "a spectrum adaptive high-performance communication system". Based on this design, the normal communication between the system and the "communication terminal" can be guaranteed under the condition of interference.

As shown in FIG. 6 , in a communication method between a spectrum adaptive high-performance communication system and a communication terminal of the present invention, the preferred steps are as follows:

(1) Real-time analysis and processing of communication signals;

(2) Communication link evaluation;

(3) Signal detection and spectrum monitoring;

(4) Adaptive adjustment of communication parameters;

(5) Adaptive communication.

The system of the present invention preferably realizes four functions including spectrum monitoring, communication link evaluation, adjustment of communication parameters, adaptive communication, etc. The details are as follows:

Communication signal real-time analysis and processing function, the preferred solution is as follows:

The intermediate frequency sampling unit first performs analog/digital conversion on the signal in the intermediate frequency. First, the channelization unit divides the working frequency band into several channels according to the channel bandwidth of the communication. The bandwidth of each channel can be changed, that is, it can be divided at equal intervals or unequal intervals. Divide. Taking equal-spaced channel division as an example, the channelization processing of D equal-spaced channels is completed by using the dynamic digital channelization technology based on polyphase filtering. The sampling rate after channelization is Fs/D, and the signal bandwidth is r*Fs/D. (r is any real number between 0 and 1), the channel spacing is 0.5Fs/D, when r is greater than 0.5, there is a certain overlapping bandwidth between the two channels; the analog/digital converted data is processed by the above channelization , according to the center frequency of each channel's independent dynamic configuration, different channels are selected as the input of subsequent processing, so as to realize the independent frequency coarse tuning of each channel; each channel has a digitally controlled oscillator (NCO) that can be independently dynamically programmed. After the complex digital mixing, the independent fine tuning function of each channel is completed; the signal after each channel has completed the coarse tuning and fine tuning function of the center frequency is input into a half-band filter, the data stream is extracted by 2 times, and the sampling of each channel is rate down to Fs/(2D).

In order to meet the seamless splicing requirements of the spectrum and the receiving requirements of large-bandwidth signals, the signal monitoring and detection functions based on the broadband spectrum, each channelization adopts the oversampling design, combined with the design of the prototype filter of the polyphase filter, can make The frequency spectrums of adjacent channels overlap to a certain extent, so that when the target signal falls at the junction of two sub-channels, it can still meet the requirements for receiving large-bandwidth signals. Taking D=8 as an example, the division of channels is shown in FIG. 3 .

Communication link evaluation function, the preferred solution is as follows:

The communication link evaluation is based on the high-performance signal reception and perception function. It performs statistical analysis on the modulation pattern, characteristic parameters, and demodulation and decoding information of the current communication signal, and evaluates the communication link in real time. The following two methods are mainly considered:

Method 1: The discrimination method based on the modulation type and characteristic parameters. Completed by the pattern recognition unit, the modulation type and characteristic parameters of the current communication signal are judged in real time to evaluate the interference situation of the communication link. Under normal communication conditions, the modulation mode and characteristic parameters of the communication signal generally do not change. Once disturbed, the modulation mode and characteristic parameters of the communication signal will change. Through the real-time statistics and analysis of these parameters, as shown in Figure 4 display, evaluating the communication link in real time.

Method 2: A judgment method based on the communication bit error rate. It is implemented by the adaptive demodulation unit, demodulates the communication signal, and evaluates the communication link in real time by judging the bit error rate. In order to facilitate bit error statistics, additional additional information needs to be added to the communication protocol, which can be channel-associated signaling, as shown in Figure 5. Since error statistics require a certain sample size, this method focuses on high-speed digital communication signals.

Signal detection and spectrum monitoring functions, the preferred solutions are as follows:

Completed by the signal detection and spectrum monitoring unit. Adaptive signal detection is a method based on software radio. Through a general hardware platform, the signal detection in the designated channel is automatically realized. When the noise floor of the communication channel is relatively flat and the noise background of the signal fluctuates little, the method is suitable. The probability of false detection and missed detection is low. The most prominent feature of communication signals is that they occupy different channels. Therefore, in most cases, the signal search is carried out in the frequency domain, that is, in a receiving frequency band, for the number of signals and parameters such as carrier frequency, bandwidth, signal-to-noise ratio Signal search and detection under unknown conditions.

Spectrum monitoring realizes instantaneous monitoring of the spectrum in the entire receiving frequency band. Therefore, the interference situation of all channel frequencies can be judged in real time, and the available frequency resource library can be updated in real time. Fig. 3 takes a certain frequency point as an example, and lists a schematic diagram of dynamic adjustment of the available frequency point resource library in the state of spectrum monitoring. In the case of spectrum monitoring, it is found that the frequency point Fs/4D (corresponding to the frequency point of channel 1) is available, and the signal detection and spectrum monitoring unit adds the frequency point Fs/4D to the available frequency point resource library, and at the same time, finds the frequency point k* Fs/4D (frequency point corresponding to channel k) is interfered. If the frequency point is in the available frequency point resource library, the signal detection and spectrum monitoring unit deletes the frequency point from the library. Other frequency points also follow this process. As shown in Figure 4.

The function of adaptively adjusting communication parameters, the preferred solution is as follows:

In a complex electromagnetic environment, the communication system is seriously interfered by other radio equipment during the communication process, and problems such as channel blockage and communication interruption occur frequently. To this end, a spectrum adaptive high-performance communication method can be used, combined with broadband signal scanning and high-performance receiving and sensing capabilities, to monitor the idle spectrum in the working frequency band in real time, evaluate the current communication link in real time, and automatically detect if the link is interfered. The switching communication strategy completes spectrum adaptive high-performance communication.

The spectrum adaptive high-performance communication strategy is mainly completed by the adaptive up-conversion module. The preferred strategies are:

Strategy 1: When the communication is interfered, the uninterrupted frequency point and available bandwidth are automatically sensed through signal detection, and the characteristic parameters of each communication signal are monitored to evaluate the interference situation of the communication link, automatically adjust the communication frequency point, and realize the spectrum automation. Adapt to high-performance communications.

Strategy 2: When the signal-to-noise ratio is low, the high-efficiency modulation mode is adopted and the communication rate is reduced to improve the bit signal-to-noise ratio (Eb/N ₀ ) and improve the communication quality.

Step 5: Adaptive communication.

The spectrum adaptive communication of the communication link will be described below by taking the receiving link as an example.

The spectrum adaptive high-performance communication system conducts self-assessment on the uplink by analyzing the modulation pattern of the communication signal and the characteristic parameter variation characteristics. Once the uplink is found to be interfered, two processing strategies are adopted: retransmission or adjustment of communication parameters:

The communication system of the present invention preferably has a retransmission strategy: after the spectrum adaptive high-performance communication system determines that the uplink is interfered, it notifies the communication terminal through a signaling channel to retransmit the frame data;

Adjust the communication parameter strategy: If the spectrum adaptive high-performance communication system adopts the retransmission strategy, after retransmitting K times (K is the number of retransmissions determined according to the communication strategy), it still cannot communicate normally, and it can be decided that the link is completely interfered. The spectrum adaptive high-performance communication system selects the available frequency points from the available frequency point resource library, notifies the communication terminal through the signaling channel, switches the working frequency point of the uplink (corresponding to the transmitting frequency point of the communication terminal), and re-establishes the communication link .

Preferably, a set of principle prototypes are used to give the preferred solution. The principle prototype is based on software radio technology and realizes functions such as broadband spectrum monitoring, signal analysis and processing, and communication through software deployment and software loading. Loading separate functional software, each function works independently, and three functional software are loaded at the same time, which can realize spectrum adaptive high-performance communication. Targeted experiments were carried out to verify this. In the test, an analog terminal is used to communicate with the principle prototype, and an external interference source is added;

The preferred solution is as follows:

(1) The principle prototype converts the communication signal sent by the analog terminal into a unified 70MHz intermediate frequency, and the intermediate frequency bandwidth is 20MHz. After the intermediate frequency is sampled, 16 channels are channelized (compared to the design case in the patent, the capacity is doubled).

(2) Real-time judgment and evaluation of the modulation pattern of the communication signal in the 16-channel channel by means of modulation pattern identification. At this time, the communication signal works at frequency point 1, the modulation pattern is BPSK modulation, and the interference source is not turned on. The terminal communicates with the principle normally, and the modulation pattern remains BPSK unchanged.

(3) The signal detection and spectrum monitoring unit performs real-time detection on the frequency points of these 16 channels. In the current case, except for frequency point 1, other 15 frequency points are available.

(4) After the interference source is turned on, add an interference signal with a different modulation pattern at frequency point 1. At this time, the pattern recognition unit recognizes the modulation pattern of the current signal as an unknown signal (UNKOWN). After three consecutive recognitions are UNKOWN, The adaptive up-conversion unit selects frequency point 2 from the available 15 frequency points, and informs the analog terminal to switch the communication signal frequency to frequency point 2.

(5) The analog terminal switches the frequency of the communication signal to frequency point 2. At this time, the pattern recognition unit recognizes the modulation of the communication signal of frequency point 2 as BPSK, and the communication between the analog terminal and the principle prototype can be continued.

Preferably, a spectrum adaptive high-performance communication method, the steps are as follows:

(1) The receiving antenna module receives the RF signal in real time from the space, and after completing the signal amplification processing, it is sent to the down-conversion module, and the down-conversion module performs down-conversion to obtain an intermediate frequency signal, which is sent to the digital channelization and processing evaluation module;

(2) The digital channelization and processing evaluation module, after performing analog-to-digital conversion on the intermediate frequency signal, obtains a digital signal, and performs channelization processing on the digital signal to obtain multi-channel channelized data;

(3) After parameter measurement and modulation pattern identification are performed on each channel of channelized data, characteristic parameters of each channel of data are obtained;

(4) performing adaptive signal demodulation and decoding according to the characteristic parameters of each channelized data to obtain demodulation and decoding information;

(5) According to the measurement results of the characteristic parameters of the channelized data of each channel, determine the identification accuracy rate of the modulation pattern;

(6) according to the demodulation decoding information of step (4), determine the demodulation bit error rate;

(7) According to the identification accuracy rate of the modulation pattern in step (5) and the demodulation bit error rate in step (6), determine the degree of interference of each channel, if it is interfered, output the interference flag, if not, output the channel The channelized data is sent to the adaptive up-conversion module;

(8) The signal detection and spectrum monitoring unit in the digital channelization and processing evaluation module detects the available frequency points of the digital signal after analog-to-digital conversion, that is, searches for the available frequency points within the set intermediate frequency bandwidth, and establishes the available frequency points The resource library is sent to the adaptive up-conversion module.

(9) The adaptive up-conversion module modulates the channelized data output from the digital channelization and processing evaluation module to the intermediate frequency bandwidth after digital-to-analog conversion according to the available frequency point resource library established by the signal detection and spectrum monitoring unit. At the available frequency points in the device, the radio frequency signal is obtained after up-conversion, and the power is amplified, and then transmitted to the space through the transmitting antenna module.

The present invention can realize a spectrum adaptive high-performance communication system with function redefinition and dynamic reconfiguration through software deployment based on a set of general hardware platforms. The system can be defined by software to realize dynamic reconfiguration and parallel application of broadband spectrum monitoring, signal analysis and processing, and communication functions. Based on the real-time and efficient signal analysis and processing capability of the wideband spectrum, the present invention monitors the communication working frequency band in real time, evaluates the communication link in real time, adaptively adjusts communication parameters and communication strategies, and switches communication frequency points in real time when the communication is interfered, thereby ensuring normal operation. It can realize spectrum adaptive high-performance communication.

The present invention effectively combines broadband spectrum monitoring, high-efficiency signal analysis and processing and communication functions, so that the communication capability of the communication system is significantly improved, and at the same time, the spectrum resource utilization efficiency of the communication system and the transmission rate of data information are also improved. An effective way to achieve "easy to use, easy to use, reliable use". The invention only uses a set of general hardware platform, and can realize the dynamic reconstruction and parallel application capability of combining the functions of wideband spectrum monitoring, signal analysis and processing, communication functions and the like in the wide bandwidth spectrum range. While significantly improving the resource utilization rate of the software and hardware platform, the system has the new technical effect of multi-functional dynamic reconfiguration and parallel application. The invention is suitable for multi-functional dynamic reconstruction and spectrum adaptive high-performance communication of communication equipment in various occasions such as ground, aviation and aerospace.

The invention is based on the wideband spectrum detection function of the signal detection and spectrum monitoring unit, and can also be used for real-time detection of interference signals in a complex and multi-interference signal environment, to determine the source of interference signals and the degree of interference, and to provide guarantees for the normal operation of communication equipment or terminals. The digital channelization and processing evaluation module of the present invention has multifunctional reconfigurability, and the functions of the channelization unit, the pattern recognition unit, the adaptive demodulation unit, the information processing and link evaluation unit, and the signal detection and spectrum detection unit are all performed by software. Realize different functions according to different software function combinations. The present invention can realize the communication function by loading channelization, information processing and link evaluation.

The present invention can realize the function of signal analysis and processing by loading channelization, modulation pattern identification, adaptive demodulation, information processing and link evaluation. The invention realizes the real-time monitoring of the broadband spectrum by loading the signal detection and spectrum monitoring, and the real-time fast detection technology of broadband multi-signal. The present invention can realize adaptive high-performance communication by loading channelization, modulation pattern identification, adaptive demodulation, information processing and link evaluation, signal detection and spectrum monitoring.

The invention combines wide-band signal scanning and high-performance receiving and sensing capabilities to monitor the idle frequency spectrum in the working frequency band in real time, and evaluate the current communication link in real time. Adapt to high-performance communications. The high-performance communication of the present invention is embodied in the broadband multi-signal fast detection technology to achieve efficient spectrum monitoring; the available frequency point resource library is established according to the monitoring results and updated in real time; the modulation pattern recognition accuracy rate and the demodulation bit error rate are used to comprehensively judge the communication interference situation. ; Preferably, the communication strategy can also be adaptively adjusted, and the frequency or communication parameters can be adjusted to ensure stable communication.

Claims (13)

1. a spectrum adaptive high-performance communication system is characterized in that comprising: a receiving antenna module, a down-conversion module, a digital channelization and a processing evaluation module, an adaptive up-conversion module, a transmitting antenna module; The receiving antenna module receives the RF signal in real time from the space, and after completing the signal amplification processing, it is sent to the down-conversion module, and the down-conversion module performs down-conversion to obtain an intermediate frequency signal, which is sent to the digital channelization and processing evaluation module; The digital channelization and processing evaluation module obtains a digital signal after analog-to-digital conversion of the intermediate frequency signal, performs channelization processing on the digital signal, and obtains multi-channel channelized data; performs parameter measurement and modulation pattern identification for each channel of channelized data After that, the characteristic parameters of each channelized data are obtained, and the adaptive signal demodulation and decoding are performed according to the characteristic parameters of each channelized data to obtain the demodulation and decoding information; according to the measurement results of the characteristic parameters of each channelized data, it is determined that the identification of the modulation pattern is correct According to the demodulation and decoding information, determine the bit error rate of demodulation; according to the recognition accuracy rate of modulation pattern and the bit error rate of demodulation, judge the interference degree of each channel, if it is interfered, output the interference mark, if not interfered, Output the channelized data of the channel and send it to the adaptive up-conversion module; The digital channelization and processing evaluation module detects the available frequency points of the digital signal after analog-to-digital conversion, that is, searches for the available frequency points within the set intermediate frequency bandwidth, establishes the available frequency point resource library, and sends it to the adaptive up-conversion module; The adaptive up-conversion module modulates the channelized data output from the digital channelization and processing evaluation module to the available frequency within the intermediate frequency bandwidth after digital-to-analog conversion according to the available frequency point resource library established by the signal detection and spectrum monitoring unit. At the frequency point, the radio frequency signal is obtained after up-conversion, and the power is amplified, and then transmitted to the space through the transmitting antenna module. 2. A kind of spectrum adaptive high-performance communication system according to claim 1 is characterized in that: digital channelization and processing evaluation module, comprising: intermediate frequency digitization unit, channelization unit, pattern recognition unit, adaptive demodulation unit , information processing and link evaluation unit, signal detection and spectrum monitoring unit. 3. a kind of spectrum adaptive high-performance communication system according to claim 2 is characterized in that: intermediate frequency digitization unit, carries out analog/digital conversion to intermediate frequency signal, obtains digital signal and sends to channelization unit, signal detection and spectrum monitoring unit. 4. a kind of spectrum adaptive high-performance communication system according to claim 2 is characterized in that: the channelization unit carries out channelization processing to the digital signal output by the intermediate frequency digitization unit, obtains the channelization data of the multi-channel signal, sends to Pattern identification unit; each channel of channelized data corresponds to the input signal of the corresponding channel. 5. a kind of spectrum adaptive high-performance communication system according to claim 2, is characterized in that: after the pattern recognition unit carries out parameter measurement and modulation pattern recognition to the multi-channel channelization data output by the channelization unit, obtains each channel of signal The characteristic parameters are sent to the adaptive demodulation unit, and the obtained channelized data are sent to the information processing and link evaluation unit at the same time. 6. A kind of spectrum adaptive high-performance communication system according to claim 2, it is characterized in that: adaptive demodulation unit carries out self-adaptation according to the characteristic parameter and corresponding channelization data of each channel signal outputted by pattern recognition unit The signal is demodulated and decoded to obtain demodulated and decoded information, and the demodulated and decoded information, signal characteristic parameters and channelization data are sent to the information processing and link evaluation unit. 7. A kind of spectrum adaptive high-performance communication system according to claim 2, it is characterized in that: information processing and link evaluation unit, according to each channelized data characteristic parameter, determine the recognition accuracy rate of modulation pattern; Modulate and decode the information to determine the demodulation error rate; according to the identification correct rate of the modulation pattern and the demodulation error rate, determine the interference degree of each channel, if it is interfered, output the interference flag, if not, output the channel's The channelized data is sent to the adaptive up-conversion module. 8. a kind of spectrum adaptive high-performance communication system according to claim 2 is characterized in that: digital channelization and processing evaluation module, also comprise: signal detection and spectrum monitoring unit, to the signal outputted by the intermediate frequency digitizing unit, based on Broadband multi-signal real-time rapid detection technology, in the intermediate frequency bandwidth according to the set frequency interval for signal detection, by judging whether the signal on each frequency point has interference, determine the available frequency points and unavailable frequency points, and establish the available frequency point resource library , and update it in real time, and send the available frequency point resource library to the adaptive up-conversion module. 9. a kind of spectrum adaptive high-performance communication system according to claim 2, is characterized in that: self-adaptive frequency up-conversion module, carries out adaptive processing according to the interference mark that signal processing and link evaluation unit output: if there is interference mark , indicating interference, select the available frequency from the available frequency resource library or adjust the communication parameters; if there is no interference, directly perform digital/analog conversion on the channelized sampling data of each channel, and the converted signal is up-converted and sent to Transmitting Antenna Module. 10. A kind of spectrum adaptive high-performance communication system according to claim 1, it is characterized in that: signal detection and spectrum monitoring unit combine down-conversion module and intermediate frequency digitizing unit, can realize the signal in the whole frequency band of communication to carry out real-time spectrum sensing, Obtain available communication frequency information, and build an available frequency resource library. 11. A spectrum adaptive high-performance communication system according to claim 1, characterized in that: an information processing and link evaluation unit, combined with a pattern identification unit, an adaptive demodulation unit, a channelization unit, and an intermediate frequency digital unit, Based on the signal analysis and processing function, statistical analysis is performed on the modulation pattern, characteristic parameters, and demodulation and decoding information of the current communication signal, so as to evaluate the communication link. 12. A spectrum adaptive high-performance communication system according to claim 1, characterized in that: the digital channelization and processing evaluation module, once it is found that the current communication link is interfered and cannot communicate normally, the adaptive up-conversion module passes the The dedicated signaling channel informs the sender and receiver of the communication link to re-select parameters such as communication frequency, communication rate, modulation mode from the available frequency library, and to re-establish the communication link. 13. A spectrum adaptive high-performance communication method, characterized in that the steps are as follows: (1) The receiving antenna module receives the RF signal in real time from the space, and after completing the signal amplification processing, it is sent to the down-conversion module, and the down-conversion module performs down-conversion to obtain an intermediate frequency signal, which is sent to the digital channelization and processing evaluation module; (2) The digital channelization and processing evaluation module, after performing analog-to-digital conversion on the intermediate frequency signal, obtains a digital signal, and performs channelization processing on the digital signal to obtain multi-channel channelized data; (3) After parameter measurement and modulation pattern identification are performed on each channel of channelized data, characteristic parameters of each channel of data are obtained; (4) performing adaptive signal demodulation and decoding according to the characteristic parameters of each channelized data to obtain demodulation and decoding information; (5) According to the measurement results of the characteristic parameters of the channelized data of each channel, determine the identification accuracy rate of the modulation pattern; (6) according to the demodulation decoding information of step (4), determine the demodulation bit error rate; (7) According to the identification accuracy rate of the modulation pattern in step (5) and the demodulation bit error rate in step (6), determine the interference level of each channel, if it is interfered, output the interference flag, if not, output the channel The channelized data is sent to the adaptive up-conversion module; (8) The digital channelization and processing evaluation module detects the available frequency points of the digital signal after analog-to-digital conversion, that is, searches for the available frequency points within the set intermediate frequency bandwidth, establishes the available frequency point resource library, and sends it to the adaptive network. frequency conversion module; (9) The adaptive up-conversion module modulates the channelized data output from the digital channelization and processing evaluation module to the intermediate frequency bandwidth after digital-to-analog conversion according to the available frequency point resource library established by the signal detection and spectrum monitoring unit. At the available frequency points in the device, the radio frequency signal is obtained after up-conversion, and the power is amplified, and then transmitted to the space through the transmitting antenna module.

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